Frank g



(No Model.)

P. G. STARK;

LOGK

No. 426.079. Patented Apr. 22, 1890.

UNITED STATES PATENT OFFICE FRANK G. STARK, OF ST. LOUIS, MISSOURI.

LOCK.

SPECIFICATION forming part of Letters Patent No. 426,079, dated Aprl 22, 1890.

Application filed March 9, 1889. Serial No. 302,'735. (No model.)

To all whom it may concc'n:

Be it known that I, FRANK G. STARK, of the city of St. Louis, in the State of Missouri, have invented a certain new and useful Improvement in Looks, of which the following is a specification.

I have devised a bolt or latch which works leverwise, with a nearly-circular ring instead of a small pivot' at the axis of motion.

My key is fiat and thin andis nnsupported at the center. It is arranged to engage with the latch by wings on opposite sides of its axis. Both the form and size of the key are essential. Any other than the proper form may not enter the key-hole, or any size materially greater or less will either not enter the ring in the latch or will enter and turn idly around in the space in the ring without operating the latch.

Such lock may be used either right hand or left hand, as circumstances or the taste of the party applying it shall render desirable.

My lock. affords a high degree of strength With cheap and easily-nade nechanism, and is peculiarly guarded against being opened by picking.

My invention may be applied in part to secure and release at will a door or other device Inovng bodily like a sliding door. It may be thus applied to secure a link at the end of a chain arranged to stretch across a passage, as across the entrance to a pew in a church or a box in an opera-house.

The following is a description of what I esteen the best means of carrying ont the invention.

Figure 1 is a front View of my lock with the front portion removed. Fig. 2 is an end View. Fig. 3 is a front view with the latch raised. Fig. 4 is a vertical section through the lock. Fig. 5 is a face view of the escutcheon and loeking-plate. This plate is shown in the raised position in dotted lines. The shaft of the key is in section. Fig 6 is a front View with the latch reversed and raised. The dotted lines in this figure show the latch depressed into position for holding the door. The remaining figures show modification& Fig. 7 is a perspective view of a modified form adapted for securing a ohain across the cntrance to a seat in church, Fig S is a section of the same. Fig. 9 is a corresponding View of the same reversed to serve on the other side of the aisle. Figs. lO and ll show modifications in the form of the key, it being understood that the casing is with each form modified to match.

Similar letters of reference indicate like parts in all the figures where they occur.

A is the door, and B the door-easing, sometimes termed the jamb, to which it is to be Secured by the lock and liberated as required. It may be understood that these parts may be of any ordinary or suitable Construction adapted to serve for dwellings, stores, workshops, or other buildings, or for the low doors used for pews in Churches, and generally for all styles and sizes of doors and gates, of whatever name, which turn upon hinges.

I have devised another form of lock which will serve for doors and gates having a sliding or endwise motion.

The description when not otherwise specially designated refers to Figs. l to 4,i11clusive.

C is 'an escutcheorplate surrounding the key-holc, and D is a casing of nalleable castiron or other suitable naterial similarly fixed byscrews or other fastenings around the keyhole on the opposite face of the door.

E is the key, having a stout ring, as nsual, for a handle, and two wings E' E at the other end to be inserted in the lock.

G is a pivoted plate analogous to an escutcheon, turning on a pivot g, set in the plate C, and having a noteh g' adapted to cngage with a collar on the key and hold the key strongly confined in the lock and door, while allowing it to be turned at will.

M is the turning or leverwise-noving bolt. I will term it a latch. Ccrtain portions will, when necessary, be marked by supernnmer` als, as M'. This latch pel-forms important functions, serving as a latch to automatically engage when the door is closed and as a locking-bolt to hold it closed until it is liberated by the key, and further serving by its form, to cramp the parts together, thus giving the device great capacity to resist violence.

M' is a ring cast or otherwise forned on one end-the end which serves as the axis of motion. M is a narrow but sufliciently stout IOO neck joining this ring to the main body M and M and M are offsets arranged as shown.

P is a guide or open-topped keeper screwed on the door, and Q is a som ewhat corresponding keeper screwed on the j amb B. The keeper Q has a projection Q' extending out from the jamb and having its upper face beveled, as shown. p

The exterior of the ring i is finished perfectly circular, excepting, of course, the junetion of the neck lVF, and is inolosed within a correspondin g circular rim D', extending more than half around it on the housing or casing D. The interval not th-us inclosed is an aperture d, in which the neck M can be moved as the latch is turned. The interier of the ring M', need not be nicely finished, but I attach much importance to its form. It is smooth and may be perfectlycircular, except that there are snoothly-rounded internal projections m 'm' 011 opposite points. These projections do not extend far inward and do not occupy the full thickness of the metal, but they are sufficient to be engaged by the rings E' E of the key E, and as the key is turned to compel the ring M', and consequently the entire latch M, to turn a partial revolution with it. This turning may be only suficient to lift the latch M out of its engagement with the keepers P and Q, allowing the latch to drop again and thus be ready to automatioally engage with the keepers when the door is again closed, or it maybe carried so far as to lift the latch into the perpendicular position and to carry it then a little farther, so that it would be held by gravity until the key should be again turned in the reverse direction to move the latch again into position to engage. It is important that the key be able to enter the key-hole, and also that it be properly formed to touch the projections m and m', and not to be obstructed in its partial-turning movement by any of the fixed parts of the casing. It is also important that the wings E' E be just sufiiciently extended, or, in other words, that the working end of the key be just sufficiently wide.

In whatI esteem the best Construction there is no center support for the key, but the center is free to move to a small eXtent up, down, and sidewise and in any intermediate direction. The key is certain to bear on both projections and to turn the latch if the right key is used, but any key cannot sucoeed unless it is of the proper form and also of a very eX- actly determined size. If it is too large it will not enter the ring M; if it is too small it can be turned idly around without moving the latch. The projections m and m' being roundcd or without shoulders, afford no abutment for ordinary picking-instruments to engage with. Their being of less thickness than the ring M' allows some picking devices to move past without exerting any force at all.

The keywings are thin, and may be plane or va'iously curved, the key-hole being correspondingly formed. I make the key-hole longer than required, so that its length affords no aid in determining the width of the key.

It will be understood that the key on being turned a half-revolution or more in the direction opposite to that required for unlocking brings the latch down afterit has been thrown into its superelevated position.

The key may always be used to pronote' the depression of the latch and insure its full and firm engagement with the keepers P and Q.

Modifications may be made without departing from the principle or sacrificing the advantage of the invention. Parts' of the invention may be used without the whole. I can dispense with the freedom of the center of the key and let the key engage by a central spur in a hole adapted to stronglysus tain it but such will increase the liability of the lock to be opened by improper instrunents, because it will not th'en be necessary to engage but one of the projections m, or m'. I can dispense with the reversible quality.

Figs. 7, 8, and 9 show a lock having my invention in part. It is arranged to secure and release a chaiu XV' to Stretch across a passage, as a pew or opera-box entrance. a chain, one end of which is permanently attached to one side of the passage. This is allowed to hang idly when not required.

' When it is desired to secure the passage, the

chain is extended across, and the link XV' at its previously-free end is inserted in the aperture d' iu the lock-case, where it acts on the beveled end M* of the lever or latch M and raises it to allow it to enter. So soon as sufficiently in, the lever bolt or latch M drops and en gages with the link W' in the obvious manner. It cannot be released again except by' the aid of the proper key inserted in the key-hole and turned with sufficient force to overcome the tension of the spring O, which aids gravity in insuring the prompt descent ot the latch. These figures show the revorsible condition very clearly. YVhen the ring M' is made with a series of steps, as in Figs. lO and ll, the internal projections m m' may be made on either one of the steps.

I claim as my invention- In a lock, the latch M, having a ring M' around its aXis of motion provided with internal projections m and m', or opposite or nearly opposite points adapted to serve with a double-winged keyE E' E as herein specified.

In testimony whereof I have he'eunto set my hand, at St. Louis, in the presence of two subscribing witnesses.

FRANK G. STARK.

XVitnesses:

THos. J. HAGGERTY, J. C. CUMMING-s.

IIO 

